Tabata Xtreme is a configurable interval timer for Tabata-style high-intensity workouts. It supports custom prepare, work, rest, rounds, sets, and rest-between-sets durations, plus presets you can save and reload. Its standout feature is "Time Warp": a multiplier that scales how fast the work interval's clock runs relative to real time, independent of rest periods. You can, for example, make a 60 second dead hang actually last 70 (or 50) seconds. Shorter times build confidence, longer ones build performance. Whether you actually tell your client about this feature is up to you! Although testing has shown that even if a person is aware of the time-warping it still helps them improve! This F-Droid build has no ads, no analytics, and no network permission.